Present day consumers typically own several electronic devices specifically designed for portability and on-the-go use, including, for example, a mobile phone or smart phone, a portable music player like an iPod® or an MP3 player, a tablet, a portable gaming unit, a camera, and the like. Each of these devices requires frequent recharging. Such electronic devices typically utilize a cable for connecting the device to a power source, such as a wall outlet, a car charger, an airplane charger, or a computer. However, a separate cable is usually required for each power source. Moreover, different electronic devices often utilize different connection ports and interfaces such that a single charging cable is not compatible with multiple devices. Accordingly, a tech-savvy consumer, with several electronic devices, will usually have multiple charging cables to keep track of. Even then, the consumer may be without sufficient power to recharge a phone due to bad weather or a power outage, or may not always be in a place where a power source is readily available, or even if so, may not have the appropriate cable or adapter available to use with a particular power source.
With traditional power sources, such as those noted above, it is often difficult to charge multiple devices at the same time, especially where each device requires a separate charging cable. For example, a car charger port may only handle a single cable at a time. Adaptor devices are available on the market for connecting multiple devices to a power source at the same time—for example, a two-to-one or three-to-one car charger splitter. However, such adapters are often only compatible with certain interfaces. Moreover, such adapters are separate from portable power sources and tend to be bulky.
Similarly, connection interface attachments are also available for adapting a charging cable for use with a variety of devices for recharging from a power source, each requiring a different interface connection. However, such attachments are usually separate small pieces, and therefore difficult to keep track of when not in use. Further, use of such attachments does not solve the problem presented by the need to charge multiple devices at the same time, from the same power source, as oftentimes, only one attachment can be used with a charging cable at a time.
Portable power chargers exist that permit recharging of electronic devices when a standard power source is not readily available. For example, portable power chargers are illustrated and described in co-pending U.S. application Ser. Nos. 13/571,992, filed Aug. 10, 2012, and 13/682,985, filed Nov. 21, 2012, which share common inventors with the present application and which are incorporated herein by reference. Some existing power charger devices usually cannot charge multiple devices at the same time, either due to limited capacity or connectivity options. Even if multiple devices may be attached to the power charger at the same time, the charger may prioritize how the devices are recharged—i.e., it will charge one device first and then the second, and so on. However, this approach takes a long time to recharge all devices and risks not having sufficient charge remaining in the charger for fully charging the second device.
Further, some portable charger devices will not permit recharging from the charger when the charger is itself being recharged or connected to an external power source. Such devices require the charger unit to be disconnected from a power source before a charge will be passed on to a device connected to the charger, or require the charger unit to be fully charged first before any device connected to the charger unit can then be recharged.
Wireless power chargers have been introduced to the market, especially for mobile electronic devices, that have provided additional approaches to recharging portable electronic devices. Such wireless power transmission devices have been developed in connection with wireless charging standardization efforts, including by the Wireless Power Consortium (WPC), which have led to the adoption of devices that permit recharging of electronic devices without the use of separate chargers for each device. More particularly, the WPC has introduced the Qi wireless charging standard. Qi, which translates to “vital energy,” takes its name from the Chinese concept of intangible flow of power and utilizes magnetic coil induction to transmit a charge from a transmitter to a receiver via a magnetic field.
Commonly, a wireless power transmission device utilizing magnetic coil induction includes a charging mat that must be connected to an external power source, such as a wall socket or a car charger socket, in order to transmit power wirelessly. The charging mat includes a transmitter having a coil. When a current is passed through the transmitter coil, a magnetic field is generated and transmitted to an electronic device placed on the charging mat. Such a device, in order to be wirelessly charged via the charging mat, must include a receiver having a coil, typically connected to the internal battery of the electronic device. When the electronic device is placed on an energized charging mat in a particular location, the receiver receives the wirelessly transmitted power in the form of a magnetic field, which induces a voltage in the receiver coil that can be used to power the electronic device or charge the internal battery of such a device.
Various drawbacks of prior art wireless power chargers have been identified. For example, such wireless chargers are not easily portable and require connection to an external power source for operation. Such external power sources are often not readily available, which makes the charger useless for on-the-go use. Additionally, some charging mat designs are often too small to be able to charge more than one electronic device at the same time. As noted, some wireless charging mats require a device to be placed in a particular spot—e.g., a Qi spot—where the transmitter and receiver coils must be aligned in order for a charge to be transmitted. Increasing the size of the charging mat may be undesirable, as it may take up too much space or be aesthetically unpleasing.
In view of the foregoing, there is a need for a charger that can be used to charge a variety of electronic devices, including but not limited to smart phones, mobile phones, data tablets, music players, cameras, camcorders, gaming units, e-books, Bluetooth® headsets and earpieces, GPS devices, and the like, either individually or simultaneously in various combinations. Additionally, there is a need for such a charger that is portable, has a compact size, and is easy to use in various conditions and locations to charge one or more electronic devices simultaneously, including but not limited to in a house or office, a car or an airplane, as well as on-the-go, without compromising operation and performance. Still further, there is a need for a portable charger that can be recharged from an external power source or from a wireless power transmission device, providing increase flexibility and convenience of use for the portable charger. Still further, there is a need for a portable charger that can recharge its internal battery from an external power source or a wireless charging device at the same time as an electronic device connected to the charger, either directly or wirelessly, is being recharged by or via the charger unit. Still further, there is a need for a portable charger unit in a compact size that has increased functionality for a user requiring a portable source of power. Accordingly, it is a general object of the present invention to provide a portable charger that improves upon conventional power chargers currently on the market and that overcomes the problems and drawbacks associated with such prior art chargers.